scholarly journals Duration of luminosity of electric discharge in gases and vapours

1913 ◽  
Vol 88 (601) ◽  
pp. 110-117
Keyword(s):  
Electric Discharge ◽  
Chemical Nature ◽  
Gaseous Mixtures ◽  
Other Substances ◽  
The Subject ◽  
Mutual Relations ◽  
Present Subject ◽  
Secondary Causes ◽  
Electric Discharge In Gases

The electric discharge produces luminosity in any gas or vapour through which it passes. The question presents itself, Does the luminosity persist after the current has ceased, or does its top immediately ? A full answer is likely to be of great importance in unravelling the cause and mechanism of the luminosity. There are exiting observations bearing on the subject, but these are somewhat scattered in the literature, and, so far as I am aware, their mutual relations have not been pointed out. It is hoped in this paper to do something towards systematising and extending them. The most conspicuous phenomena in this connection are the various forms of afterglow which have been discussed in previous papers. But these are not really relevant to tire present subject, for they are due to secondary causes of a chemical nature. Some of them, produced in gaseous mixtures containing oxygen, are due to the interaction of ozone with other substances present. Others, again, are connected with the formation of an active modification of nitrogen. In none of these cases can the after-luminosity be considered continuous with the luminosity of tire discharge which produced it. For it is always much less brilliant, even at first, and always has a quite different spectrum.

On Hereditary Insanity

1864 ◽  
Vol 10 (49) ◽  
pp. 50-66 ◽  
Author(s):  
Hugh Grainger Stewart
Keyword(s):  
Medical Literature ◽  
Early Period ◽  
Fundamental Principle ◽  
Perfect Knowledge ◽  
The Subject ◽  
Indian Tribes ◽  
Falling Sickness ◽  
Transmission Of Disease ◽  
Secondary Causes

The hereditary transmission of disease, or of a tendency to it, has of late attracted more attention than it formerly did, and medical literature has been enriched by many able and learned disquisitions on the subject. Its importance seems to be generally appreciated, to a certain extent, but not to so great an extent, as a more perfect knowledge of its operation, and the vastness of its influence, would justify. From Burton's ’Anatomy of Melancholy’ may be quoted many passages by ancient writers, showing a lively appreciation of the fact of hereditary transmission, especially of disease. Fernelius says, “Such as the temperature of the father is, such is the son's, and, look, what disease the father had when he begot him, his son will have after him, and is as well the inheritor of his infirmities as of his lands.” “And where the complexion and constitution of the father is corrupt, then,” saith Roger Bacon, “the complexion and constitution of the son must needs be corrupt, and so the corruption is derived from the father to the son.” Burton also quotes passages from Hippocrates, Buxtorfius, Lemnius, Paracelsus, Crato, Bruno Seidelius, Daniel Sennertus, Forestus, Rodericus a Fonseca, Lodovicus Mercatus, and many others, referring to hereditary transmission, or the transmission of melancholy. The last mentioned wrote a book on the subject, ‘De Morbis Hereditariis,’ and therein first notices what is now called atavism. “It skips, in some families, the father and goes to the son, or takes every other, and sometimes every third, in a lineal descent, and doth not always produce the same, but some like, and a symbolising disease.” This last remark is of importance, as anticipating a fundamental principle in modern investigations into the subject. Burton himself highly estimates the importance and power of hereditary transmission, when he says, “These secondary causes, hence derived, are commonly so powerful that (as Wolphius holds) they do often alter the primary causes and decrees of the heavens.” This most learned and far-seeing author mentions facts, and hints at conclusions which are only now being understood and arrived at, and shows that an appreciation of the truth of hereditary transmission had formed the basis of laws forbidding the marriage between persons in any whit allied, and of those stern and implacable decrees, which, among certain Indian tribes, and even in Scotland, at an early period, necessitated the destruction of those that suffered from madness, gout, falling sickness, or any such dangerous diseases.

scholarly journals Physico-Chemical Investigations in the Amide Group

1906 ◽  
Vol 25 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Charles E. Fawsitt
Keyword(s):  
Aqueous Solutions ◽  
Carboxylic Acids ◽  
Amide Group ◽  
Chemical Dynamics ◽  
Physico Chemical ◽  
Other Substances ◽  
The Subject

Some time ago, while studying the chemical dynamics of the changes which occur in solutions of urea or carbamide, I came upon some rather unexpected results which led me to hope that investigations conducted on somewhat the same lines with other substances of the amide group might prove to yield results of some interest. The amides referred to are those derived from carboxylic acids. While proceeding to this investigation I noticed some measurements, obtained in connection with the viscosity of aqueous solutions of carbamide, which appeared of sufficient interest to demand an inquiry into the nature of solutions of this class of substances before proceeding further with the subject of inquiry in the manner at first intended.

III. Experimental researches in electricity. ─Twenty-fifth series

1851 ◽  
Vol 141 ◽  
pp. 29-84 ◽  
Keyword(s):  
Magnetic Force ◽  
Central Line ◽  
General View ◽  
Axial Line ◽  
Electric Induction ◽  
Other Substances ◽  
Iron Nickel ◽  
The Subject ◽  
Experimental Researches ◽  
As If

2797. The remarkable results given in a former series of these researches (2757. &c.) respecting the powerful tendency of certain gaseous substances to proceed either to or from the central line of magnetic force, according to their relation to other substances present at the same time, and yet the absence of all condensation or expansion of these bodies (2756.) which might be supposed to be consequent on such an amount of attractive or repulsive force as would be thought needful to produce this tendency and determination to particular places, have, upon consideration, led me to the idea, that if bodies possess different degrees of conducting power for magnetism, that difference may account for all the phenomena; and, further, that if such an idea be considered, it may assist in developing the nature of magnetic force. I shall therefore venture to think and speak freely on this matter for a while, for the purpose of drawing others into a consideration of the subject; though I run the risk, in doing so, of falling into error through imperfect experiments and reasoning. As yet, however, I only state the case hypothetically, and use the phrase conducting power as a general expression of the capability which bodies may possess of affecting the transmission of magnetic force; implying nothing as to how the process of conduction is carried on. Thus limited in sense, the phrase may be very useful, enabling us to take, for a time, a connected, consistent and general view of a large class of phenomena; may serve as a standard of meaning amongst them, and yet need not necessarily involve any error, inasmuch as whatever may be the principles and condition of conduction, the phenomena dependent on it must consist among themselves. 2798. If a medium having a certain conducting power occupy the magnetic field, and then a portion of another medium or substance be placed in the field having a greater conducting power, the latter will tend to draw up towards the place of greatest force, displacing the former. Such at least is the case with bodies that are freely magnetic, as iron, nickel, cobalt and their combinations (2357. 2363. 2367. &c.), and such a result is in analogy with the phenomena produced by electric induction. If a portion of still higher conducting power be brought into play, it will approach the axial line and displace that which had just gone there; so that a body having a certain amount of conducting power, will appear as if attracted in a medium of weaker power, and as if repelled in a medium of stronger power by this differential kind of action (2367. 2414.).

Sociological Imagination and Literary Sensitivity: A Tribute to M. N. Srinivas

2019 ◽  
Vol 68 (2) ◽  
pp. 133-153
Author(s):  
N. Jayaram
Keyword(s):  
Sociological Imagination ◽  
Social Anthropology ◽  
Raja Rao ◽  
Rare Combination ◽  
The Subject ◽  
Mutual Relations ◽  
The Way

M. N. Srinivas is undoubtedly the most readable among sociologists in India. For him, the way he wrote about a subject was as important as the subject itself. This lent a literary flavour to his writings. His writings are, in fact, imbued with a rare combination of sociological imagination and literary sensitivity; The Remembered Village, his masterpiece is perhaps the best illustration of this. In his Hassan Raja Rao Lecture, titled ‘Social Anthropology and Literary Sensibility’ (1998), he explained the relevance and importance of such sensitivity for sociologists engaged in understanding society and culture. Taking a cue from this, the instant lecture examines the mutual relations between sociological imagination and literary sensitivity. Substantively, it elucidates the sociological imagination embedded in literature and the consequent importance of literature for the sociologist.

scholarly journals IX. On some hitherto undescribed optical properties of doubly refracting crystals.—Preliminary notice

1878 ◽  
Vol 26 (179-184) ◽  
pp. 384-386 ◽  
Keyword(s):  
Royal Society ◽  
Focal Point ◽  
The Body ◽  
Index Of Refraction ◽  
Double Refraction ◽  
Other Substances ◽  
The Subject ◽  
Microscopical Society ◽  
Royal Microscopical Society

In the Proceedings of the Royal Society (vol. xxiv. p. 393) Dr Royston-Pigott described a new refractometer to determine the index of refraction of liquids and other substances by means of the displacement of the focal point of an object seen through them with a low magnifying-power. Another paper on the subject was communicated by him to the Royal Microscopical Society, and subsequently published its Journal. After the reading of this paper I said that it appeared me probable that the same principle might be applied with advantage the determination of the index of refraction of minerals. The chief question was how to make the requisite measurements by means of such a addition to an ordinary microscope as would not in any way interfere with its general use for other purposes. This I accomplished by fixing graduated scale to the body of the microscope and a vernier to the supporting arm, so that the position of the focal point can be read off to within about 1/2000 of an inch. I described this arrangement and pointed out its value in connexion with mineralogy at a meeting of the Mineralogical Society last March, and an account of it was published in the Journal of the Society. I have since learned that a very similar addition was made to a microscope in Professor Clifton’s laboratory at Oxford some eight years ago, and used for the measurement of the index of refraction of glass, but no account of it was ever published. When I came to study the index of refraction of doubly refracting minerals I was very soon struck with the fact that, instead of seeing at one focus the two systems of lines at right angles to each other, they were sometimes quite invisible, or one set was seen at one focus, and the whether at a very different, as though they had been ruled on the two opposite sides of a piece of glass. These curious phenomena were exhibited at the soirée of the Royal Society on the 25th of April last, and Processor Stokes immediately examined the question theoretically, and found that they could be explained by, and might have been predicted from, the known laws of double refraction, though apparently no one had ever studied them, either theoretically or practically. We therefore decided to investigate the problem independently. I was to make the practical observations, and he to give the theoretical explanations, the results being kept separate, but communicated conjointly to the Royal Society.

scholarly journals VIII. The Bakerian Lecture.—Experimental of laws of magneto-electric induction in different masses of the same metal, and of Intensity in different metals

1833 ◽  
Vol 123 ◽  
pp. 95-142 ◽  
Keyword(s):  
Great Difficulty ◽  
The Other ◽  
Present Purpose ◽  
Electric Induction ◽  
Other Substances ◽  
The Subject ◽  
The Absolute ◽  
Experimental Researches

Mr. Faraday's highly interesting papers, entitled “Experimental Researches in Electricity,” having been referred to me, to report on, by the President and Council of this Society, I necessarily entered minutely into all the experiments and conclusions of the author, and the more so that I had had the advantage of witnessing many of the most important of these experiments. It is foreign to my present purpose to descant upon the value of Mr. Faraday’s discovery, or the merits of his communication ; the President and Council have marked their opinion of these by the award of the Copley Medal: but I may be permitted to state, that no one can concur more cordially than I do in the propriety of that award. Agreeing as I did generally with the author, both in the views which he took of the subject, and in the conclusions which he drew from his experiments, there was one, however, which I felt great difficulty in adopting, viz. “That when metals of different kinds are equally subject, in every circumstance, to magneto-electric induction, they exhibit exactly equal powers with respect to the currents which either are formed, or tend to form, in them :" and that “the same is probably the case in all other substances.” Although the experiments might appear to indicate that this was possibly the case, I did not consider them to be conclusive. The most conclusive experiment, that of two spirals, one of copper and the other of iron, transmitting opposite currents, was quite consistent with the absolute equality of the currents excited in copper and iron; but, at the same time, the apparent equality of the currents might be due to their inequality being counteracted by a corresponding inequality in the facility of transmission.

On the chemical nature of a wax from China

1851 ◽  
Vol 5 ◽  
pp. 754-756
Keyword(s):  
Chemical Nature ◽  
Soap Solution ◽  
The Subject ◽  
General Appearance

The wax which is the subject of this investigation, is a substance imported into this country from China. It has the general appearance of spermaceti, but is harder than that body. The author gives reasons for believing that this wax, like bees’-wax, is a secretion from an insect. The wax may be decomposed by fusion with hydrate of potash, by which process two substances are procured; namely, a wax acid, which, combined with the potash, forms a soap; and another body which is dissolved in the soap solution. By precipitation with chloride of barium and washing out the dried baryta salt with ether, or other suitable solvents, the two substances may be separated.

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